Furnace



March 10. 1925. 1,529,587-

J. G ODFR EY FURNACE Filed March 3, 1924 4 Sheets-Sheet 1 NVENTOR ATTORN EY March 10. 1925. I 1,529,587

J. GODFREY FURNACE Filed March 5, 1924 4 Sheets-Sheet 2 '3 fiaafrey' INVENTOR ATTORNEY ATTORNEY 4 Sheets-Sheet 4 .NVENW.

J. GODFREY FURNACE Filed March 3, 1924 March 10. I925.

Patented Mar. 10, 1925.

UNITED STATES JAMES GODFREY, OF PITTOCK, PENNSYLVANIA.

FURNACE.

1 Application filed March 3, 1924. Serial No. 696,710.

To all whom it may concern:

Be it known that 1, JAMES GODFREY, a citizen of the United States, residing at Pittock, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Furnaces, of which the following is a specification.

This invention relates to furnaces, and more particularly to a furnace specially adapted for heating slabs and ingots for use in rolling mills.

One of the main objects of the invention is to provide a furnace of the character stated of simple construction and high efiiciency in which recuperators are employed, simple and efficient means being provided for reversing the direction of draft so as to employ or utilize the heat of either recuperator desired. A further object is to provide a furnace of this character in which the combustion chamber is open at both ends to permit the ingots or slabs to be fed into and discharged from the furnace, means being provided for causing a sheet of flame to extend across each of the end openings so as to prevent access of air to the ingots or slabs and increase combustion. Another object is to provide a furnace of this type having simple and eflicient means for removing scales, clinker-s, etc., from the combustion chamber. Further objects will appear from the detail description.

In the drawings 2- Figure 1 is a side view of the furnace;

Figure 2 is. a top plan view;

Figure. 3 is a horizontal section taken.

' of the main casing being broken away;

Figure 5 is a section taken substantially on line 55' of Fig. 4:;

Figure 6 is a diagrammatic view showing the direction of fidw ofthe air and the products of combustion when the control dampers are in one position";

i I o 0 re 7 1s a similar view showing the.

Fi direc t i on of flow of air and the products of combustion when the control dampers are in the other position.

The furnace includies a main casing 1 above which is supported a roof 2 which includes two downwardly and inwardly inclined sections 2 connected at their inner ends by an upwardly curved arch 2*. A hood Sis provided at each end of roof 2, this hood being curved inwardly and of substantially semi-circular shape in crosssection. Hood 3 is extended from a boxing 4 disposed transversely of roof 2 and a plurality of burners 5 of any suitable or preferred type, extend across this boxing and project through openings 5 provided through the inner wall of the boxing adjacent to the inner edge of hood 3, these burners being directed toward the curved inner surface 3 of the hood. \Vhen the burners are operating the curved surface 3 of the hood causes a sheet of flame to pass downwardly across each of the openings 6 and 6 at the ends of the combustion chamber. This effectually prevents air from entering the combustion chamber and also causes air to be drawn through openings 6 and 6*, this air mixing with the flames so as to produce more complete combustion. materially increasing the heat produced within the combustion chamber. The flames flow inwardly toward the center of the combustion chamber from each end thereof.

Opening 6 provides means'whereby ingots or slabs may be fed into the furnace, these ingots or slabs being pushed into the furnace by means of a ram A, or in any other suitable or preferred manner, along rails 7 mounted in the upper edges of skid walls 8 which extend longitudinally of the combustion chamber in parallel spaced relation. After the ingots or slabs have been heated to the desired temperature they pass through opening 6 onto a car placed be-' neath this opening. This provides a furnace of continuous operation in which the slabs or ingots may be continuously fed through the furnace, the sheets of flames extending across the openings 6 and 6* effectually preventing entry of air into the combustion chamber and the air which mixes with the flames materially increasing combustion.

The skid walls 8 are supported by spaced ribs 9 which extend transversely of the bottom of the combustion chamber, the upper faces of these ribs being of inverted V-shape. The ribs 9 are disposed in parallel spaced relation, and the spaces between these ribs form troughs 10 which receive.

the scales which drop from the ingots or slabs, any ash or other foreign materials which are not consumed in the combustion chamber being also directed into the troughs to the combustion chamber when desired or necessary.

At the center of the combustion chamber I provide a transverse bridge wall 13 provided at its upper end with a cap 13 of inverted flattened V-shape. At each side of this wall I provide a passage 14 which communicates bymeans of a slot 15 with the interior of the ,combustion chamber centrally thereof. One of the passages 14 is in communication with a checker chamber 16 within which is a checker 17 of a known construction, the other passage 14 communicating with a checker chamber 18 within which is a checker 19, these checker chambers being formed together and enclosed by the recunerator casing 20. A division wall 21 extends across the front of the checker phambers 16 and 18 and a horizontal partition 22 extends from wall 21 to front wall 23 of the recuperator casing 20, wall 23 extending from the bottom wall 20 of casing 20 to the top wall 20 of the casing. This provides a space 24 with which communicates a conduit 25 which is connected to a stack 26. A stack damper 27 is mounted in conduit 25, this damper being operated by a cable 28 passing over apulley 29 mounted in a bracket 30 secured upon a suitably {positioned support 31. The space between walls 21 and 23 and above partition wall 22 forms a housing 32 for two pairs ofqdampers 33 which are slidable between guide'strips 34, partition wall 22 being provided with slots to accommodate these dampers and the dampers being disposed transversely of space or passage 24. The dampers 33 are arranged in pairs,

the dampers of each pair being secured to the ends of a cable '35 which passes over a pulley 36' rotatably mounted in a bracket 37 secured on the top wall 20 of recuperator casing 20. An outlet opening 38 is provided through wall 21 at each side of wall 16 of checker chamber 16, these openings establishing communication between the respective checkers and the space or. passage 24. The dampers 33 are ar ranged in pairs adjacent the sidesof each of the openings 38. Space 24 communicates, at each end, by means of openings 39 throu h wall 23 with a conduit 40 of in-- verte U-sha e which extends about and over the sta'c conduit 'or flue 25. A main conduit 41 communicates with conduit 40 centrally thereof, this main conduit being connected by supplemental conduits 42 to the boxings 4. Air inlet pipes 43 are positioned in the outlet passages 14 of easing 1, these pipes being connected to a fan so as to discharge air from either of the pipes 43, optionally, into the checker chamber with which this pipe communicates. I

In practice, the burners 5 are ignited, after which air is discharged through one of the air inlet pipes 43 into the correspond ing checker chamber, a portion of the products of combustion being caused to flow' through this checker chamber and the checker therein, this portion of the products of combustion mixed with the air discharged from the pipe being returned to boxings 4 and discharged through openings 5 about the burners 5. This insures pre-heating of the air and also obtains complete combustion of the fuel while producing an intense 'heat. The remaining portion of the products of combustion is drawn through the other checker chamber and the checker thereinand-fiows through flue 25 to stack 26. WVith the dampers 33 in the positions illustrated in Figures 4 and 5, air is discharged from the left-hand pipe 43, as

considered in Figures 3, 4 and 5, into checker chamber 16. This induces a portion of the products of combustioiv from the central portion of the casing through the lefthand passage 14, this portion of the products o combustion mixing with the air and the mixture flowing downwardly through checker 17 and through the opening 38 which communicates with this checker into the space or passage 24, the mixture of air and gases then flowing upwardly through the left hand portion of conduit 40 into the main conduit 41 and thence to the boxings 4 by means of the supplemental or branch conduits 42. With the stack damper 27 in its normal or raised position, a draft is created through checker 19 so that theremaining portion of the products of combustion is drawn through the other passage 14 and flows downwardly through checker 19. these products then flowing through the other opening 38 into space 24 and through flue 25 to the stack 26. By reversing the positions of the dampers 33 and connecting the fan to the other air pipe 43, the operation above described is reversed. The flow of the products of combustion, and the mixture of air and products of combustion, will be clear from the diagrams. shown in'Figs. 6 and 7 in which the feathered arrows indicate the direction of flow of the mixture of air and products of combustion, the plain rection of flow of the products of combustion unmixed with air. This provides a and complete combustion of the fuel used is obtained so as to produce intense heat. The flames from burners 5 prevent air from entering the combustion chamber, as these flames form a sheet which extends across the openings 6 and 6, while acting to induce a supplemental air supply into the combustion'chamben which becomes th0roughly intermingled with the unconsumed particles of fuel thus insuring complete combustion. By reversing the, direction .of travel of the flames, by means of the downwardly: and inwardly carved inner surfaces 3 of hoods 3, and providing the downwardly and inwardly inclined portions 2 of roof 2, the flames are caused to flow downwardly and inwardly toward the center of the combustion chamber from each end thereof. At the central portion of the chamber the oppositely flowing flames meet and commingle in the space provided by arch 2 any unconsumed particles .of fuel which may be contained in the flames being consumed at this portion thus producing intense heat at the center of the furnace.

This insures quick and uniform heating of the ingots or slabs to a high temperature thus effecting a material saving in time as well as in fuel consumed.

What I claim is 1. In a furnace of the character described, a main casing including a combustion chamber open at its ends, the inner surface of the roof of the casing being curved downwardly and inwardly of the casing above 7 the respective'openings, burne rsdisposed' to cause the products ofcombustion to impinge against the curved. surfaces of the casing so as to reverse the direction of travel.

of the flames after leaving the burners causing the flames to pass across the openings and inwardly and downwardly of the combustion chambers from each end thereof, and means for withdrawing the products of combustion from the combustion chamber centrally thereof.

2. In a furnace of the character described, a main casing including a combustion chamber open at its ends, the roof of the casing being inclined downwardly from each end toward its centre and provided with an arch connecting the inner ends of the inclined portions of the roof, hoods at each end of the roof above said openings and having their inner faces curved downwardly and intardly of the casing, burners disposed to direct the flames from the burners against the curved surfaces of the hoods, the

- hoods acting to reverse the direction-of the flames so as to direct them downwardly aiid inwardly of the combustion chamber from the ends thereof and across said openings, and means for withdrawing the products of combustion from the combustion chamber centrally thereof.

'3. In a furnace of the character described, a main casing including a combustion chamber open at its ends, hoods above the openings and having their inner faces curved downwardly and inwardly of the combustion chamber, boxings adjacent to the inner sides of the hoods, burner's extending into the hoods froln the boxings, the boxings being provided with openings surrounding said burners, a recuperator including two checkers, and means for withdrawing the products of combustion from the combustion chamber centrally thereof through either checker, optionally, and for supplying air through the other check-er to said boxings. 1

4. In a furnace of the character described, a main casing including a combustion cham} ber open at its ends, hoods alfove the openings and having their inner faces curved downwardly and inwardly. ofthe combustion chamber, boxings adjacent to the inner sides of the hoods, burners extending-into ing provided with openings surrounding said burners, a recuperator including two checkers, and means for withdrawing a portion of the products of combustion from' the combustion chamber centrally through either checker, optionally, and for withdrawing the remainder of the products of combustion through the other checker, said means acting to supply air to the other checker and toreturn said remainder of the products of combustion together with the air to said boXings.

5. In a furnace of the character described, a casingincluding a combustion chamber, boxings at the ends of the combustion chamber, burners passing through the boxings into the combustion chamber, the boxing-s be ing provided with openings surrounding the burners and 'comnnlnicating with the com-. bustio-n chamber, a recuperator including two checkers, and means for withdrawing a portion of the products of combustion from the combustion chamber cent-rally thereof through either checker. optionally, and for withdrawing the remainder of the products of combustion through the other checker, said means acting to supply air to the other checker and to return said remainder of the products of combustion together with the air to said boxings. i

6. In a furnace of the character described, acasing including a combustion chamber, boxings at the ends of the combustion chamber, burners passing through the boxings into the combustion chamber, the boxings being provided with openings surrounding thereof pressure to either of said passages, optional- 1y, a stack,.and means for establishing communicationbetw'een said stack and the outlet 0t either checker and for connecting the outlet of the other checker to saidboxi ngs.

7. In a furnace of the character described,

.a casing including a combustion chamber, boxmgs at the ends of the combustion chamfiber, burners passing through the-boxings perator casing, the checker chambers being into the combustion chamber, the boxings' being provided with openings surrounding the burners and communicating with the combustion chamber, a recuperator casing including two checker chambers and a passage extending across one end of the recuprovided with outlets opening into the said passage, a conduit communicating with said passage at the ends thereof, a main conduit communicating with the first mentioned conduit and with saidboxings, a fine communieating with the passage between the ends thereof, dampers arranged in pairs at opposite sides of the-outlet openings of the respective checker chambers and adjustable to close or open the passage of the recuperator casing, a bridge Wall at the centre of the I main casing, said main casing being provided with outlet passages at opposite sides of the brldge wall communicating with the combustion chamber and the respectivechecker chambers, and means for discharg ing air under pressure into either of the outlet passages, optionally', in the direction of the. checker, chamber with which said p as-' sage communicates.

In testimony whereof I affix my signature.

' JAMES GODFREY. 

